This trial is designed to test the safety, immunogenicity, and clinical activity of autologous peripheral blood dendritic cells (DCs) pulsed with tumor-derived idiotype protein in patients who have undergone high dose therapy and stem cell rescue for B cell lymphomas and multiple myeloma. The long-term goal of this study is to develop a vaccine therapy which will induce a clinically effective immune responses. The vaccine is produced on a custom basis from each patient's tumor cells and peripheral blood dendritic cells. In pilot studies in lymphoma, cellular immune responses and tumor regressions have been observed.